1.
Area of shaded region,
=(Area of bigger circle) - (Area of smaller circle)
=πR^2 - πr^2
=π ( R^2 - r^2 )
=3.14 ( 8^2 - 4^2)
=3.14 × ( 64 - 16 )
=3.14 × 48
=150.72 cm^2
2.
Area of shaded region,
=(Area of big semi-circle) - ( Area of small semi-circle)
=(πR^2)/2 - (πr^2)/2
=π/2 ( R^2 - r^2 )
=3.14/2 ( 6^2 - 3^2 )
=1.57 × ( 36 - 9 )
=1.57 × 27
=42.39 cm^2
HOPE THIS WILL HELP YOU
